Shchepkin Daniil V, Nikitina Larisa V, Bershitsky Sergey Y, Kopylova Galina V
Institute of Immunology and Physiology, Russian Academy of Sciences, Yekaterinburg 620049, Russia.
Institute of Immunology and Physiology, Russian Academy of Sciences, Yekaterinburg 620049, Russia.
Biochem Biophys Res Commun. 2017 Aug 19;490(2):324-329. doi: 10.1016/j.bbrc.2017.06.043. Epub 2017 Jun 13.
Myocardium of mammals contains a wide range of isoforms of proteins that provides contractile function of the heart. These are two isoforms of ventricular and two of atrial myosin, α- and β-tropomyosin, and two isoforms of α-actin: cardiac and skeletal. We believe that the difference in the amino acid sequence of α-actin can affect the calcium regulation of the actin-myosin interaction. To test this hypothesis, we investigated effects of the isoforms of α-actin, cardiac and skeletal, and the isoforms of cardiac myosin on the calcium regulation of the actin-myosin interaction in an in vitro motility assay using reconstructed regulated thin filaments. The results show that isoforms of α-actin and the ratio of α/β-chains of Tpm differently affect the calcium regulation of the actin-myosin interaction in myocardium in dependence on cardiac myosin isoforms.
哺乳动物的心肌包含多种蛋白质同工型,这些同工型赋予心脏收缩功能。它们是心室肌球蛋白的两种同工型、心房肌球蛋白的两种同工型、α - 和β - 原肌球蛋白,以及α - 肌动蛋白的两种同工型:心肌型和骨骼肌型。我们认为,α - 肌动蛋白氨基酸序列的差异会影响肌动蛋白 - 肌球蛋白相互作用的钙调节。为了验证这一假设,我们在使用重组调节细肌丝的体外运动分析中,研究了心肌型和骨骼肌型α - 肌动蛋白同工型以及心肌肌球蛋白同工型对肌动蛋白 - 肌球蛋白相互作用的钙调节的影响。结果表明,α - 肌动蛋白同工型和原肌球蛋白α/β链的比例根据心肌肌球蛋白同工型的不同,对心肌中肌动蛋白 - 肌球蛋白相互作用的钙调节有不同影响。